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Background: Diabetic retinopathy is one of the complications of diabetes mellitus. The aim of this study was to explore the effects of ubiquitin-specific protease 48 (USP48) and its underlying mechanisms in the development of diabetic retinopathy. Methods: CCK-8 assay, EdU assay, and flow cytometry were used to measure the proliferative ability and the apoptotic rate of ARPE-19 cells, respectively. ELISA kits were utilized to assess the levels of inflammatory cytokines. The levels of Fe2+, ROS and MDA were detected using the corresponding biochemical kits. The protein expression of USP48 and SLC1A5 was examined through western blot. The mRNA level of SLC1A5 was determined using RT-qPCR. The interaction relationship between USP48 and SLC1A5 was evaluated using Co-IP assay. Results: High glucose (HG) treatment significantly inhibited cell proliferation and elevated cell apoptosis, inflammation, ferroptosis and oxidative stress in ARPE-19 cells. HG treatment-caused cell damage was hindered by USP48 or SLC1A5 overexpression in ARPE-19 cells. Fer-1 treatment improved HG-caused cell damage in ARPE-19 cells, which was blocked by USP48 knockdown. Moreover, USP48 knockdown decreased SLC1A5 expression. SLC1A5 downregulation reversed the improvement effects of USP48 upregulation on cell damage in HG-treated ARPE-19 cells. Conclusion: USP48 overexpression deubiquitinated SLC1A5 to elevate cell proliferation and suppress cell apoptosis, inflammation, ferroptosis and oxidative stress in HG-triggered ARPE-19 cells, thereby inhibiting the progression of diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Based on the Quick Access Recorder (QAR) data covering over 9000 routes in China, the monthly and intra-day distribution characteristics of aircraft bumpiness at different levels were analyzed, and the relationships between the eddy dissipation rate (EDR) and other aircraft flight status elements during bumpiness occurrence were also analyzed. Afterward, aircraft bumpiness routes were constructed using 19 machine learning models. The analyses show that (1) aircraft bumpiness was mainly concentrated between 0:00 a.m. and 17:00 p.m. Severe aircraft bumpiness occurred more frequently in the early morning in January, especially between 5:00 a.m. and 6:00 a.m., and moderate bumpiness always occurred from 3:00 a.m. to 11:00 a.m. (2) The relationship between the left and right attack angles and aircraft bumpiness on the routes was more symmetrical, with a center at 0 degrees, unlike in the approach area where the hotspots were mainly concentrated in the range of −5 to 0 degrees. In the approach area, the larger the Mach number, the more severe the bumpiness. (3) The performances of the Automatic Relevance Determination Regression (ARD), Partial Least Squares Regression (PLS), Elastic-Net Regression (ENR), Classification and Regression Tree (CART), Passive Aggressive Regression (PAR), Random Forest (RF), Stochastic Gradient Descent Regression (SGD), and Tweedie Regression (TWD) based models were relatively good, while the performances of the Huber Regression (HUB), Least Angle Regression (LAR), Polynomial Regression (PLN), and Ridge Regressor (RR) based models were very poor. The aircraft bumpiness prediction models performed best over the approach area of ZBDT (airport in Datong), ZULS (airport in Lhasa), ZPPP (airport in Kunming), and ZLQY (airport in Qingyang). The model performed best in predicting the ZLLL-ZBDT air route (flight routes for Lanzhou to Datong) with different prediction times. [ABSTRACT FROM AUTHOR]

Introduction: Our previous work indicated that the activation of the Toll-like receptor (TLR) 4 signaling pathway contributed to noise-induced cochlear inflammation. Previous studies have reported that low-molecular-weight hyaluronic acid (LMW-HA) accumulates during aseptic trauma and promotes inflammation by activating the TLR4 signaling pathway. We hypothesized that LMW-HA or enzymes synthesizing or degrading HA might be involved in noise-induced cochlear inflammation. Methods: The present study included two arms. The first arm was the noise exposure study, in which TLR4, proinflammatory cytokines, HA, hyaluronic acid synthases (HASs), and hyaluronidases (HYALs) in the cochlea as well as auditory brainstem response (ABR) thresholds were measured before and after noise exposure. The second arm was analysis of HA delivery-induced reactions, in which control solution, high-molecular-weight HA (HMW-HA), or LMW-HA was delivered into the cochlea by cochleostomy or intratympanic injection. Then, the ABR threshold and cochlear inflammation were measured. Results: After noise exposure, the expression of TLR4, proinflammatory cytokines, HAS1, and HAS3 in the cochlea significantly increased over the 3rd to 7th day post-noise exposure (PE3, PE7). The expression of HYAL2 and HYAL3 dramatically decreased immediately after noise exposure, gradually increased thereafter to levels significantly greater than the preexposure level on PE3, and then rapidly returned to the preexposure level on PE7. The expression of HA, HAS2, and HYAL1 in the cochlea remained unchanged after exposure. After cochleostomy or intratympanic injection, both the hearing threshold shifts and the expression of TLR4, TNF-α, and IL-1β in the cochleae of the LMW-HA group were obviously greater than those of the control group and HMW-HA group. The expression of proinflammatory cytokines in the LMW-HA and control groups on the 7th day (D7) after cochleostomy tended to increase compared to that on the 3rd day (D3), whereas levels in the HMW-HA group tended to decrease on D7 compared to D3. Conclusion: HAS1, HAS3, HYAL2, and HYAL3 in the cochlea are involved in acoustic trauma-induced cochlear inflammation through the potential proinflammatory function of LMW-HA. [ABSTRACT FROM AUTHOR]

Graph theory has found significant use in chemistry, especially in modelling chemical structures. A molecular graph can be represented by a graph where atoms represent vertices and links between these atoms are called edges. Each molecular structure has its own physical properties, such as boiling point, melting point, density, molecular mass, entropy, etc. A topological invariant of a molecular structure is a descriptor that is correlated to certain chemical and biological actions of the chemical compounds. In this paper, we studied the structure of oxide networks, triangular silicate networks, dominating oxide networks and dominating silicate networks in connection to some additive degree-based topological indices. Specifically, the ranking among these networks is also determined with the help of certain multi-criteria decision-making techniques (MCDM). In the end, regression and correlation analyses between their chemical properties and topological indices has been observed. [ABSTRACT FROM AUTHOR]

The new generation of spaceborne laser altimeter, the Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2), which can simultaneously generate laser reflections on the water surface and underwater, is a potential data source for exploring water depth in nearshore environments. To achieve this scientific goal, accurate bathymetric photon extraction is needed. This study proposed a pre-pruning quadtree isolation (PQI) method with changing threshold. Firstly, the pre-pruning step is introduced. Photons are transformed into different levels in the isolated quadtree structure according to spatial density. Then, the frequency histogram of photon elevation and isolated level (IL) is generated, the IL thresholds in different depth ranges are calculated by the Otsu method, and the bathymetric photons are extracted. The results in the Culebra archive show that this method achieved a 92.71% F1 score. Noise rate and water depth are the main factors affecting the extraction of sounding photons. When the photon density gradually increases from 2–4 pts/m to 6–8 pts/m, the F1 score of PQI decreases by no more than two percent. In different depth ranges, the extraction results of PQI are also better than those of comparison methods. Therefore, PQI can provide reliable theoretical support for nearshore areas lacking water depth data. [ABSTRACT FROM AUTHOR]

In this paper we study the time-dependent discrete nonlinear Schrödinger equation with complex, not necessarily bounded, potential and sufficiently general nonlinearity on a multi dimensional lattice. Under natural assumptions we prove the global well-posedness in weighted l 2 spaces. In the dissipative case we obtain a result on the existence of global compact attractor in such spaces. [ABSTRACT FROM AUTHOR]

All-polymer solar cells (all-PSCs) are organic solar cells in which both the electron donor and the acceptor are polymers and are considered more promising in large-scale production. Thanks to the polymerizing small molecule acceptor strategy, the power conversion efficiency of all-PSCs has ushered in a leap in recent years. However, due to the electrical properties of polymerized small-molecule acceptors (PSMAs), the FF of the devices is generally not high. The typical electron transport material widely used in these devices is PNDIT-F3N, and it is a common strategy to improve the device fill factor (FF) through interface engineering. This work improves the efficiency of all-polymer solar cells through interfacial layer engineering. Using PDINN as the electron transport layer, we boost the FF of the devices from 69.21% to 72.05% and the power conversion efficiency (PCE) from 15.47% to 16.41%. This is the highest efficiency for a PY-IT-based binary all-polymer solar cell. This improvement is demonstrated in different all-polymer material systems. [ABSTRACT FROM AUTHOR]

Chemical graph theory is a multidisciplinary field where the structure of the molecule is analyzed as a graphical structure. Chemical descriptors are one of the most important ideas employed in chemical graph theory; this is to associate a numerical value with a graph structure that often has correlation with corresponding chemical properties. In this paper, we investigate another very important closed-packed usual crystal structure defined as HCP (Hexagonal Close-Packed) crystal structure and its lattice formed by arranging its unit cells in a dimension for topological descriptors based on a neighborhood degree, reverse degree, and degree. Furthermore, we classify which descriptor is more dominating. [ABSTRACT FROM AUTHOR]

Topological indices are numerical numbers assigned to molecular graphs and are expected to predict certain of its physical or chemical properties. Metal-organic frameworks (MOFs) are inorganic/organic porous crystalline materials with a regular array of positively charged metal ions which surrounds organic linkers. Covalent organic frameworks (COFs) are a class of organic polymers with highly ordered structure and permanent porosity. In this work, we have computed some degree-based topological indices of naphthalene metal-organic frameworks and thiophene-based covalent triazine framework. [ABSTRACT FROM AUTHOR]

The recent rise of high-risk scenarios such as unmanned aerial vehicles and intelligent driving, which require low latency and high privacy, has given rise to a new field called Federated Learning (FL). Limited communication bandwidth becomes a major bottleneck for aggregating local models in FL. Therefore, we use fast global model aggregation based on over-the-air computation (Aircomp). Wireless data transmission consumes most of the power of the edge nodes compared with the energy consumption required for sensing and processing data. Optimizing the transmission power of nodes can significantly save system power. To the best of our knowledge, in most of the research works on FL, the optimum design of system parameters usually takes the peak power of each sensor as the constraint condition. In this paper, the sum power constraint of edge devices is innovatively proposed to minimize the aggregation error of FL. We also study the optimization problem to minimize the total power of all edge sensors in the FL system under certain aggregation error constraints. Unfortunately, these problems presented are nonconvex biquadratic programming problems that are very difficult to solve. Therefore, we propose an alternative optimization method based on the difference-of-convex algorithm. The numerical results show that our proposal significantly reduces the aggregation error under the same total power. The simulation results also show that Intelligent Reflector Surface-assisted communication can greatly reduce the aggregation error and save system power. [ABSTRACT FROM AUTHOR]

Modern endometritis therapeutics may require an extremely precise and controlled drug release system. Poly lactic-co-glycolic acid (PLGA) microspheres loaded with two different drugs like amoxicillin and vancomycin were prepared and their efficacy in management of endometritis in murine model was examined. Such biological nanocarriers are need of the hour since they are biodegradable, cytocompatible, hemocompatible and easily formulated. The sizes of the drug loaded PLGA microspheres ranged from 65–100 nm. The electron microscopy images depicted them as uniform spherical structures. The zeta potential and polydispersity index were calculated and the in vitro release investigation indicated steady drug release over a period of 50 h at effective dosage. The drug loaded nanocarriers were found with be cytocompatible and hemolysis test elaborated that they met with hemolysis rate safety requirements. The murine models were induced with endometritis by intravaginal administration of bovine uterine isolates. The mice were sacrificed and histopathogical examination of the endometrial slides stained with haematoxylin and eosin revealed that the drug loaded PLGA nanospheres helped in reducing acute endometritis in mice in a very short time. This study thereby demonstrated well described synthesis approach of drug loaded PLGA nanospheres which may be further be transferred to preclinical laboratory studies. [ABSTRACT FROM AUTHOR]

Introduction: Synovial sarcoma (SS) is a rare mesenchymal malignant tumor. SS of the spine or retroperitoneum is an extremely rare site. Approximately 30% cases show focal calcifications on radiographs and computed tomography (CT) images, while extensive calcification rarely occurs. We presented a case of SS involving the spinal canal and paraspinal muscle and retroperitoneum, which showed extensive calcification on CT. Clinical presentation: The present report describes the case of a 13-year-old girl suffering from a tumor in the spinal canal and paraspinal muscle and retroperitoneum with extensive calcification on CT. The patient underwent lumbar and retroperitoneal giant tumor resection, lumbar decompression, and spinal tumor resection with a small tumor remnant remaining in the paravertebral region. Histological examination and genetic testing after surgery confirmed synovial sarcoma. After surgery, the patient refused local radiotherapy but agreed to receive chemotherapy. After 4 months of follow-up, her condition was basically stable, and the pain in her left lower limb disappeared. The residual tumor was not increased. Conclusion: Extensive calcification of SS is rare. The possibility of synovial sarcoma should be considered in those who show extensive calcification in the spinal canal and paraspinal muscle and retroperitoneum on CT. For cases that cannot be completely resected, adjuvant chemotherapy can control the residual tumor in the short term. In addition, the long-term effects need to be observed. [ABSTRACT FROM AUTHOR]

In order to analyse the impact of renewable generation and load uncertainties on the economic operation optimization of the island microgrid, a multiobjective economic optimal dispatch model under uncertainty based on interval optimization is proposed in this paper. The mathematical model of distributed generation and the prediction model of wind speed and wave generation are established. The uncertainties of renewable generation and load are described by the interval mathematical method. On this basis, the interval multiobjective optimal dispatch model is presented. For the "battery disgusting" users on the island, the battery cost is regarded as a separate optimization objective, and a multiobjective optimization objective function to minimize the economic cost, battery cost, and pollution emission of the island microgrid is discussed. An island microgrid, composed of wind turbine, photovoltaic, wave energy generation, diesel generator, and energy storage system, is chosen as a case study. The NSGA-II algorithm is applied to solve the multiobjective optimal problem. The results for deterministic forecast data and load are analysed, and the optimal operation scheme is obtained by the improved multiobjective grey target decision-making method. The influence of renewable generation fluctuations ±10%, ±20%, and ±30% and the load fluctuations ±10% and ±20% on island microgrid operation optimization is discussed in detail, respectively. The relevant research results can provide a reference for formulating the operating scheme of the island microgrid. [ABSTRACT FROM AUTHOR]

In this paper, we study the normal mode solutions of 3D incompressible viscous fluid flow models. The obtained theoretical results are then applied to analyze several time-stepping schemes for the numerical solutions of the 3D incompressible fluid flow models. [ABSTRACT FROM AUTHOR]

In this paper, an automatic RGBD object segmentation method is described. The method integrates depth feature with the cues from RGB images and then uses maximal similarity based region merging (MSRM) method to obtain the segmentation results. Firstly, the depth information is fused to the simple linear iterative clustering (SLIC) method so as to produce superpixels whose boundaries are well adhered to the edges of the natural image. Meanwhile, the depth prior is also incorporated into the saliency estimation, which helps a more accurate localization of representative object and background seeds. By introducing the depth cue into the region merging rule, the maximal geometry weighted similarity (MGWS) is considered, and the resulting segmentation framework has the ability to handle the complex image with similar colour appearance between object and background. Extensive experiments on public RGBD image datasets show that our proposed approach can reliably and automatically provide very promising segmentation results. [ABSTRACT FROM AUTHOR]

The objective of this research was to study the precipitation of Sb and the stability of Sb2S3 during treatment of synthetic Sb(V) wastewater by sulfate-reducing bacteria (SRB). We investigated the transformation and precipitation of Sb, as well as the re-dissolution of Sb2S3 under different pH and carbon sources. The results showed that the precipitation of aqueous Sb and the re-dissolution of Sb2S3 depend on the conversion between Sb(III)-S(-II) complexes and Sb2S3 precipitates. These processes were highly pH-dependent, and a decrease in pH enhanced reduction of Sb(V) and precipitation of Sb2S3 were observed. The newly formed Sb2S3 was found to be unstable and could re-dissolve through complexation with H2S due to the increase in pH. When pH decreased to approximately 6.5, Sb was almost completely transformed into Sb2S3 precipitates, and the Sb2S3 precipitates were relatively stable. Compared with lactate as a carbon source, ethanol resulted in a comparable H2S yield and a relatively low pH and was, therefore, more conducive to the removal of Sb(V). The results of this study suggest that when removing Sb(V) in wastewater by SRB, it is important to control the pH at a relatively low level. [ABSTRACT FROM AUTHOR]

Microgrid is an effective way to utilize renewable energy resources, especially for satisfying the electricity requirements in remote islands. The operation optimization of an island microgrid is critical to ensure the effective performance of the whole microgrid system, and it is usually a multiconstrained and multiobjective optimization problem. The main contribution of this study is an operation optimization method for the stand-alone microgrid system in a remote island, which includes wind, PV, battery, and diesel generator. In this paper, a novel operation optimization model for stand-alone microgrid is proposed, in which the battery system is considered separately; the multiobjective day-ahead optimization model considering economic cost, battery depreciation cost, and environmental protection cost is established. In the optimization, the output power of diesel generator and energy storage system are chosen as the decision variables. For this purpose, an efficient search algorithm combining the particle swarm optimization (PSO) algorithm and the simulated annealing (SA) algorithm is developed. The hybrid algorithm is applied to search for the Pareto solution set of the optimization problem. The search results are compared with those from traditional PSO algorithm. Also, a grey target decision-making theory based on the entropy weight method is proposed to identify the best trade-off scheduling scheme among all the solutions, and the results are compared with those from two other commonly used subjective and objective methods. The results show that the proposed optimization method can be applied to the day-ahead operation optimization of the microgrid system and help the user obtain the best compromise operation scheme for stand-alone microgrid. [ABSTRACT FROM AUTHOR]

• RMSFFA geopolymers showed good F-T resistance after 50F-T cycling. • 50 °C and 14-day curing are more favorable conditions for better F-T resistance. • Micro-cracks and gel dissolution likely caused RMSFFA's mechanical deterioration. Freeze-thaw (F-T) durability of geopolymers synthesized from the mixture of red mud slurry-Class F fly ash (RMSFFA) was investigated in this study, with an emphasis on the influence of curing conditions (i.e., curing time and curing temperature). F-T durability was evaluated on the basis of the sustained mechanical strength of RMSFFA geopolymer specimens after subjected to 50F-T conditioning cycles. The change in their chemical bonding, mineralogy, and pore characteristics at various F-T conditioning cycles was examined with Fourier transform infrared spectroscopy, X-ray diffractometer, and Brunauer–Emmett–Teller testing, respectively, to reveal the underlying processes during F-T conditioning. The results of both mechanical strength and microstructural characterization indicate that curing conditions influence F-T resistance of RMSFFA geopolymer samples through affecting their strength development. For 14-day cured RMSFFA samples at 50 °C, they experienced further geopolymerization at the early stage of F-T conditioning but the partial dissolution of geopolymer gel at the later stage of F-T conditioning. For 28-day cured samples at 50 °C, only the partial dissolution of geopolymer gel was likely to occur during the F-T conditioning because the strength development was likely to complete prior to the conditioning. [ABSTRACT FROM AUTHOR]

The TLR-4/NF-κB signaling pathway is involved in innate immunity and inflammation induced by trauma. The present study aimed to investigate possible TLR-4/NF-κB signaling pathway activation in the cochlea associated with acoustic trauma that might induce cochlear inflammation. A total of 72 rats were exposed to white noise at 120 dB SPL for 8 h per day repeated over 2 successive days. Auditory brainstem responses (ABR) were measured in animals before noise exposure and 0 d (PE0), 1 d (PE1), 3 d (PE3), 7 d (PE7), and 14 d (PE14) after noise exposure. At each defined time point, animals were sacrificed, and cochleae were collected to evaluate the expression levels of TLR4, MyD88, cytoplasmic NF-κB p65, IκBα, TNF-α, and IL-1β using western blotting and NF-κB p65 transcriptional activity using an NF-κB p65 Transcription Factor Assay Kit. Cochlear localizations of TLR-4, TNF-α and IL-1β were analyzed using immunohistochemistry in paraffin-embedded slices. The nuclear translocation of NF-κB p65 was evaluated using immunofluorescence staining in paraffin-embedded slices. DNA fragmentation was measured with a TUNEL assay in paraffin-embedded slices. We found a stable permanent threshold shift after noise exposure. After noise exposure, expression levels of TLR-4, MyD88, IκBα, TNF-α, and IL-1β were significantly upregulated (PE3); DNA binding activity of NF-κB p65 was also significantly enhanced (PE3), while the cytoplasmic NF-κB p65 levels were unchanged. TLR-4, TNF-α, and IL-1β immunostaining intensities were substantially enhanced in spiral ganglion cells and spiral ligament fibrocytes after noise exposure (PE3). In conclusion, the results of this study indicate that the TLR-4/NF-κB signaling pathway is activated in noise-exposed cochleae and that it participates in noise-induced cochlear inflammation. • TLR-4 and the downstream signaling molecule MyD88 were significantly upregulated 3 d after noise exposure. • IκBα of NF-κB, and downstream molecules of TNF-α, IL-1β, and MCP-1 were significantly upregulated 3 d after noise exposure; the nuclear translocation of NF-κB p65 increased in the lateral wall, spiral limbus, and spiral ganglion 3 d after noise exposure. • Expression levels of TNF-α and IL-1β in the spiral ganglion and spiral ligament peaked 3 d after noise exposure. [ABSTRACT FROM AUTHOR]

Objective: To investigate the protective effects and underlying mechanisms of Vitamin C (VC) on hydrocortisone (HC)-induced cell injury in human microvascular endothelial cells (HMEC). Methods: Cell viability was measured by CCK-8 assay and the expression of Best-3 was detected by Western blotting assay. The experiment was divided into normal control, HC injury group, VC treatment groups, HC + Best-3 siRNA group, HC + VC + Best-3 siRNA group, HC + pcDNA3.1 Best-3 group, and HC + VC + pcDNA3.1 Best-3 group. Results: HC inhibited HMEC-1 cell viability was balanced with lower expression of Best-3 in a dose-dependent manner. Conversely, VC promoted HMEC-1 cell viability was paralleled to higher expression of Best-3 in a dose-dependent manner. Silencing Best-3 with Best-3 siRNA inhibited HMEC-1 cell viability, however, over-expression of Best-3 with pcDNA3.1 Best-3 promoted HMEC-1 cell viability. Moreover, VC and over-expression of Best-3 prevented HC-induced HMEC-1 cell apoptosis; however, silencing Best-3 further enhanced HC-induced HMEC-1 cell apoptosis. HC reduced Best-3 expression, which was alleviated by VC treatment. HC treatment decreased Bcl-2 expression, facilitated Bax expression. Both of VC and over-expression of Best-3 promoted Bcl-2 expression and decreased Bax expression. Additionally, VC and Best-3 expression have a synergistic effect. Conclusions: VC can efficiently attenuate HC-induced HMEC-1 cell injury, which may be related to promote Best-3 expression. [ABSTRACT FROM AUTHOR]

The refraction phenomenon causes ICESat-2 nearshore bathymetry errors by deviating seafloor photons' coordinates. A refraction correction method based on ATL03 photon parameter tracking was proposed to improve the ICESat-2 bathymetry accuracy. The method begins by searching for sea–air intersections using photon parameters. Instead of relying on mathematical operations, it uses logical relations to establish a relationship between the seafloor and the surface, which improves efficiency. Then, a refraction correction model is designed based on Snell's law for different sea surface fluctuations. This model is clear and suitable for scholars new to refraction correction. The results show the effectiveness of the proposed method since the RMSE is reduced by 1.8842 m~5.2319 m compared with the raw data. Our method has better tolerance than other methods at different water depth ranges. [ABSTRACT FROM AUTHOR]

Here we report a new member of in-plane anisotropic 2D materials Rhenium Diselenide (ReSe 2) which holds a stable distorted 1 T' phase with its relatively narrow bandgap to explore the in-plane anisotropic structural, electrical, and optical properties. The proposed polarization-sensitive photodetectors based on few-layer ReSe 2 provides highly anisotropic photodetection behavior with linearly dichroic ratio up to ≈2.62 under 808 nm illumination. We measured carrier transport in space and time by mapping carrier density in a ReSe 2 plate using transient absorption microscopy. These results directly determined the carrier diffusion coefficients of about 4100 cm2 s-1 and 2900 cm2 s-1 along the armchair and zigzag directions, respectively, providing fundamental parameters to better understand the anisotropy of ReSe 2 and promote future 2D optoelectronic applications in polarization-sensitive detection. [ABSTRACT FROM AUTHOR]

Primitive neuroectodermal tumors (PNETs) are rare malignant neoplasms in the spinal cord that comprise undifferentiated or poorly differentiated neural crest cells. PNETs imaging findings lack specificity, making diagnosis difficult. A 16-year-old male patient presented with progressive weakness and numbness of the lower extremities for 1 month, which occurred after a cold. Significantly elevated protein levels were detected in his cerebrospinal fluid. Magnetic resonance imaging revealed multiple patchy or spindle-shaped hyperintensities on T2-weighted imaging, which is similar to acute myelitis imaging findings. However, the effect of hormone treatment was minimal. Enhanced magnetic resonance imaging with gadolinium-diethylenetriamine pentaacetic acid showed significant enhancement of intramedullary lesions and the meninges, which was diagnosed as tuberculosis and tuberculous meningitis. After therapy with quadruple antituberculosis treatment for 1 week, however, the T-spot was negative. Therefore, the antituberculosis regimen was ceased. Atypical cells were observed in cerebrospinal fluid from a third lumbar puncture. Next, most of the thoracic intramedullary lesions were resected. By histopathology, these lesions manifested as PNETs. This paper reports a very rare case of PNETs with multiple lesions in the spinal cord that mimicked acute myelitis and emphasizes that multiple PNETs lesions detected by magnetic resonance imaging could have an initial acute myelitis-like presentation, which should be considered a differential diagnosis. [ABSTRACT FROM AUTHOR]

A new classification scheme based on the gradient boosting decision tree (GBDT) algorithm is developed to improve the accuracy of rain area delineation for daytime, twilight, and nighttime modules using Advanced Himawari Imager on board Himawari-8 (AHI-8) geostationary satellite data and the U.S. Geological Survey digital elevation model data. The GBDT algorithm is able to efficiently manage the nonlinear relationships among high-dimensional data without being affected by overfitting problems. The new delineation module utilizes several features related to the physical variables, including cloud-top heights, cloud-top temperatures, cloud water paths, cloud phases, water vapor, temporal changes, and orographic variations. The scheme procedure is as follows. First, we perform extensive experiments to optimize the module parameters such that the equitable threat score (ETS) reaches its maximum value. Then, the GBDT-based modules are trained and classified with the optimum parameters. Finally, validation datasets are applied to test the true performance of the GBDT-based modules. The agreement between the estimations and observations of the ground-based rain gauges is verified. Results show that the ETS values of the GBDT-based modules are 0.42 for the daytime, 0.30 for the twilight period, and 0.32 for the nighttime. The cloud water path and cloud phase features make the most significant contributions to the modules. Comparisons drawn with the two probability-related methods show that our new scheme presents great advantages in terms of statistical scores on the overall performance. [ABSTRACT FROM AUTHOR]

We investigated the remediation of wastewater containing As and Sb through the application of a mixed culture of sulfate-reducing bacteria (SRB). The effect of Fe(II) and different carbon sources on the removal of As and Sb was evaluated. The wastewater initially contained 5 mg L −1 of both As(V) and Sb(V), and the treatment was conducted over a 12-d period. The produced precipitates were characterized by TEM and XRD to elucidate the metalloid removal mechanism. In the absence of Fe(II), Sb was efficiently removed (97.6% and 97.8% with lactate and ethanol as carbon sources, respectively, hereinafter the same), whereas only a relatively small fraction (27.8% and 26.4%) of As was removed. The addition of 200 mg L −1 Fe(II) greatly improved the removal of As (78% and 98.2%) and further increased the removal of Sb (98.8% and 99.4%). We hypothesized that As was removed through sorption/co-precipitation by FeS instead of the formation of As 2 S 3 . The use of ethanol as a carbon source generated a relatively lower yield of sulfide compared to the use of lactate, but it resulted in a higher removal of As and Sb. This may be attributed to the low production of sulfide, which possibly resulted in the slow precipitation of FeS that enhanced the sorption/co-precipitation of ions. This work demonstrates the high application potential of ethanol as a carbon source and the addition of Fe(II) in the bioremoval of As and Sb from wastewater by SRB. [ABSTRACT FROM AUTHOR]

Alginate/polyacrylamide hybrid hydrogel has attracted intense interests in different fields, but the low tensile strength and stiffness limit its comprehensive application. In this hydrogel system, the alginate-cation network plays an important role. Thus, based on the unique structure of alginate and its special interaction with different metal cations, we designed a new method of introducing barium and ferric ions together to crosslink the alginate sufficiently, creating a stronger alginate network. As a result, the prepared hybrid hydrogel exhibits enhanced strength and stiffness, which may serve as a new way to develop stronger hydrogel. [ABSTRACT FROM AUTHOR]

Nitrogen/sulfur co-doped and hierarchical porous graphene hydrogels (DHGHs) are prepared by facile self-assembly process. The results show that the pH values of preparation process significantly affect the microstructures and electrochemical properties of DHGHs and the mechanism has been discussed. The as-prepared DHGHs can be directly used as binder-free electrodes to assemble full-cell supercapacitor devices. It is surprising that the DHGHs prepared at basic condition (DHGH-12) delivers a specific capacitance of 251 F g −1 (0.5 A g −1 ). Moreover, the DHGH-12 shows rectangular cyclic voltammetry shape at a high scan rate of 3000 mV s −1 and symmetrical galvanostatic charge/discharge curves at 100 A g −1 which exhibits a specific capacitance of 136.5 F g −1 , a high energy density of 4.74 Wh kg −1 and high power density of 25.47 kW kg −1 . Additionally, DHGH-12 presents superior cycling stability (96.8% retention after 2000 cycles at 20 A g −1 ) in 6 M KOH solution. Therefore, the novel DHGHs can be considered as promising candidate for high energy density supercapacitors at high rates. [ABSTRACT FROM AUTHOR]

In two-dimensional (2-D) direction-of-arrival (DOA) estimation, paring the azimuth and elevation angles of multiple sources is an important issue. In this letter, we propose a new automatically paired 2-D DOA estimation method by designing the geometry of two antenna subarrays and using the propagator method (PM). A special geometry between two parallel uniform linear arrays (ULAs) with a position displacement on the axial direction is proposed to facilitate the elevation and azimuth pairing and estimation. The simulation results have shown that the proposed method can achieve the same 2-D DOA estimation performance as the existing methods, while the complexity is reduced considerably. [ABSTRACT FROM AUTHOR]

A series of chiral thioureas derived from quinine were tested as catalysts in the enantioselective Michael additions of nitromethane to α,β -unsaturated ketones containing pyridine. The best results were obtained with the bifunctional catalyst prepared from 3,5-di(trifluoromethyl)-aniline under solvent-free conditions. This thiourea promoted the reaction with high enantioselectivities and chemical yields for aryl ketones. The origins of enantioselectivity were further investigated via experiment and computation. Meanwhile, the products from our reaction showed potent antibacterial activities against rice bacterial leaf blight, with the S -enantiomer performing much better than the R -enantiomer. Given the promising bioactivity of this class of molecules, our work is expected to offer important applications in developing future generations for drug design. [ABSTRACT FROM AUTHOR]

Via the radical polymerization of 2-(dimthylamino) ethyl methacrylate in the polyacrylic acid solution, we obtain the dually pH-reponsive polyelectrolytes complex hydrogel, which could be triggered to be swollen either in acid and basic environments. The results show that the responsive behavior of these PEC hydrogels is insensitive to monomer concentration in the prepolymerization, but can be tuned by changing the charge ratio or introducing chemical crosslinker. Moreover, other amazing propertise of the prepared PEC hydrogel are presented, which are including the ionic strength-responsiveness, the modest mechanical property (a tensile stress of 0.2 MPa and a tensile strain of 1500%) and the self-healing ability (a self-healing efficiency of ca. 70%). In brief, we report a multi-functional hydrogel which might serve as a new platform for responsive materials. [ABSTRACT FROM AUTHOR]

Bioremediation of metal(loid)-contaminated water could be a cost-effective process. In this work, Sb-polluted water was treated by application of a mixed batch culture of sulfate-reducing bacteria (SRB). Aqueous Sb could be efficiently removed by the SRB over an initial pH range 5–8. The SRB was tolerant of at least 50 mg L −1 Sb in solution. With an initial pentavalent Sb (Sb(V)) concentration of 5 mg L −1 , batch kinetic variations of the treatment were studied over a 11 d period at an initial pH 7 at 30 °C. A high removal (93%) of the aqueous Sb was achieved. The final products were identified microscopically. Before removal of Sb from solution in this treatment, Sb(V) was first reduced to trivalent Sb (Sb(III)). Hydrogen sulfide was proven to be the reducing agent in this reaction. The SRB were not able to reduce Sb(V) enzymatically. Following the chemical reduction of Sb(V) to Sb(III), the latter reacted with excess sulfide, resulting in the formation of insoluble antimony sulfide (Sb 2 S 3 ). Studies on the sorption of Sb species by dead SRB indicated that, in the batch treatment, sorption by bacteria made a relatively small contribution to the removal of Sb. [ABSTRACT FROM AUTHOR]

A novel bridged organosilane precursor with star-shaped construction, [hexfluoropropane-2,2-diyl)dibenzyl-bridged organosilane (HFPDBO)], is prepared by facile organic synthesis method. The resultant HFPDBO precursor is mixed with porogen and acid catalyst to prepare periodic mesoporous organosilica (PMO) thin film via evaporation-induced self-assembly after spin-coating procedure. All the as-prepared HFPDB-based PMO thin film has been characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectrum, scanning electron microscopy, transmission electron microscope, and small-angle X-ray diffraction, respectively. Thereinto, the HFPDB-based PMO thin film with weight ratio of porogen to precursor (0.75:1) possesses excellent dielectric property (1.58@1 MHz of dielectric constants), high mechanical property (5.54 ± 0.11 GPa of Young's modulus) and hydrophobic property (90.1° of water contact angle) simultaneously. These low dielectric constant, high mechanical strength, and the hydrophobicity suggest potential application of the HFPDB-based PMO thin films as low-k materials in microelectronics. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to develop and validate a risk score for predicting combined extracranial and intracranial artery stenosis (EICAS) in acute ischemic stroke patients. Methods Patients with acute ischemic stroke were consecutively and prospectively enrolled in this study. Eligible patients were randomly divided into derivation and validation cohorts. Variables collected at presentation were used for predicting EICAS after acute ischemic stroke. Multivariable logistic regression was used to identify independent risk factors. Points for EICAS were generated by β-coefficients. Sensitivity and specificity of the risk score was assessed by the area under the receiver operating characteristic curve (AUROC). Cutoff value for predicting EICAS was determined by maximum Youden index. Results There were 629 patients with EICAS and 352 patients without cranial artery stenosis. Among EICAS, 321 patients were in the derivation cohort and 308 in the validation cohort. Five independent predictors including age, diabetes mellitus, hypertension, Low density lipoprotein (LDL) and heart disease were used to develop a 10-point score. The score was termed ADLH2 (age, diabetes mellitus, hypertension, LDL, heart disease).The ADLH2 showed good discrimination in the derivation (AUROC 0.695; 95% confidence interval, 0.656–0.735) and validation (AUROC 0.672; 95% confidence interval, 0.631–0.712) cohort. The cutoff value at maximum Youden index was 4 with the sensitivity 0.479 and specificity 0.719. Stroke patients with ADLH2 score ≥ 4 need further examination and therapy for EICAS. Conclusions The ADLH2 score is a valid risk score to identify high-risk EICAS individuals who need further investigation and treatment. [ABSTRACT FROM AUTHOR]

The optical response of various geometrical metallic nanoshell with silica are investigated by CST Microwave Studio ® simulation. Farfield optical properties such as extinction cross section and enhancement of electric field on different geometrical surface are presented. The positions of plasmon absorptions near shorter and longer wavelength are also altered as changing the dimension parameters. Distorted irregular shapes NPs enormously enhance electric field as compared to regular NPs. Some particular simulation result is also compared to previously published work done by the method of Finite Difference Time Domain (FDTD) and Mie Theory. Assembles of NPs with different geometry size and shape are helpful in modeling multiple detected nano-antenna within optical frequency range. [ABSTRACT FROM AUTHOR]

In this study, chemiluminescence (CL) behaviour of Luminol-H2O2in the presence of the different concentrations of four surfactants, cetyltrimethylammonium bromide (CTAB), cetylpyridinium bromide (CPB), sodium dodecyl sulphate (SDS) and polyoxyethylene dodecyl ether (Brij-35), was investigated. A novel method for the direct determination of critical micelle concentration (CMC) of the surfactants using flow-injection CL is described. Under the optimum conditions, the luminescence intensity of the Luminol-H2O2system increased gradually with increasing concentration of the surfactants before the CMC, but rapidly reached to the emission maximum at the CMC, followed by a decrease after the CMC. The concentrations of the surfactants corresponding to the luminescence maximum are in agreement with the literature CMC values. The main factors affecting the determination of CMC are discussed. The mechanistic studies show that the luminescence peaks observed in the experiment were mainly because of the protective effect of the micelle against the transition of the excited species and the retarding effect of the micelle structures on the CL reaction rate. [ABSTRACT FROM PUBLISHER]

This paper reports a novel wet chemical etching method, referred to as uniform metal-assisted chemical etching (MaCE), for uniform hole formation in fabrication of through silicon vias (TSVs) on silicon (Si) interposer in wafer level. In MaCE, a layer of Au as catalyst is deposited on the photolithography-patterned Si surface. Uniform holes are formed by simply immersing the Au-loaded Si into a hydrofluoric acid-hydrogen peroxide aqueous solution. In a typical experiment, \sim 1 million holes are formed after MaCE for 4 h at room temperature over a 4-in Si wafer with a diameter of 28 \mu \text{m} , a depth of 162 \mu \text{m} , a pitch size of 80 \mu \textm , and a sidewall roughness below 50 nm. The holes show high geometric uniformity in wafer level, with their depth in the range 159–164 \mu \textm , the diameter in 27.1– 29.7 ~\mu \textm , and high verticality. Simultaneous etching of two wafers in the same batch is also demonstrated. The TSV etched by MaCE show compatibility with SiO2 deposition by plasma-enhanced chemical vapor deposition and copper filling by electroplating. The reported method provides an approach for manufacturing TSV on Si interposer with simple operation, high geometric uniformity, high throughput, and low cost. [ABSTRACT FROM AUTHOR]

To solve the problem of template update in biometric recognition system at regular time, this paper presented a template update method in biometric recognition system.Firstly, it described the self-update and co-update algorithms.Then, it made a theoretical analysis of self and co-update performance by exploiting the path-based clustering approach.Finally, it proposed the update method based on path-based clustering and unsupervised template.The experiments on the large DIEE multimodal data set show that the proposed method can update the template in biometric recognition system effectively.Moreover, the results show that the performance of co-update is superior to that of self-update by a simulative model. [ABSTRACT FROM AUTHOR]

Intelligent reflective surface (IRS) and unmanned aerial vehicle (UAV) communication are two key technologies in the sixth generation of mobile communication (6G). In this paper, IRS is equipped on UAV to form aerial IRS, which can achieve 360° panoramic full-angle reflection and flexible deployment of IRS. In order to achieve high-quality and ubiquitous network coverage under data privacy and low latency requirements, we propose an Federated learning (FL) network via Over-the-Air computation (AirComp) in IRS-assisted UAV communications. Our goal is to minimize the worst-case mean square error (MSE) by jointly optimizing the IRS phase shift, denoising factor for noise suppression, the user's transmission power, and UAV trajectory. Optimizing and quickly adjusting the UAV position and IRS phase shift, it flexibly assists the signal transmission between users and base stations (BS). In order to solve this complex non-convex problem, we propose a low-complexity iterative algorithm, which divides the original problem into four sub-problems, respectively using the semi-definite programming (SDP) method, slack variable introduction method, successive convex approximation (SCA) method to solve each sub-problem. Through the analysis of simulation results, our proposed design scheme is obviously better than other benchmark schemes. [ABSTRACT FROM AUTHOR]

The Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2), launched in September 2018, has been widely used in forestry and surveying. A high-accuracy digital elevation model (DEM)/digital surface model (DSM) for terrain matching can effectively evaluate the ICESat-2 design requirements and provide essential data support for further study. The conventional terrain-matching methods regard the laser ground track as a whole, ignoring the individual differences caused by the interaction of photons during flight. Therefore, a novel terrain-matching method using a two-dimensional affine transformation model was proposed to describe the deformation of laser tracks. The least-square optimizes the model parameters with the high-accuracy terrain data to obtain the best matching result. The results in McMurdo Dry Valley (MDV), Antarctica, and Zhengzhou (ZZ), China, demonstrate that the proposed method can verify geolocation accuracy and indicate that the average horizontal accuracy of ICESat-2 V5 data is about 3.86 m in MDV and 4.67 m in ZZ. It shows that ICESat-2 has good positioning accuracy, even in mountainous areas with complex terrain. Additionally, the random forest (RF) model was calculated to analyze the influence of four factors on geographic location accuracy. The slope and signal-to-noise ratio (SNR) are considered the crucial factors affecting the accuracy of ICESat-2 data. [ABSTRACT FROM AUTHOR]

Phosphate may affect the behavior of metal(loid)s in environments, so the interaction of Sb(III) with FeS affected by phosphate was investigated in this study. Sb(III) was reacted with synthesized FeS in solution at pH 5.5, 7.0, and 9.0 with and without the addition of phosphate. The concentrations of Fe(II), Sb(III), and phosphate in the solution were monitored, and the solid phases were examined by XRD, TEM, and XPS. For the interaction of Sb(III) with FeS in the absence of phosphate, the formation of Sb 2 S 3 was very important at pH 5.5 and 7.0, whereas Sb(III) adsorption was the dominant process at pH 9.0. The interaction of Sb(III) with FeS could be significantly affected by phosphate, and this impact was dependent of pH and phosphate concentration. At pH 5.5 and 7.0, the effect of phosphate varied markedly with increasing phosphate concentration. Low phosphate loadings (9.5 and 19 mg/L) had a negligible effect on the mobility of Sb(III), while high phosphate loadings (95 and 475 mg/L) notably enhanced the uptake of Sb(III) by FeS. In the case of high phosphate loadings, Fe 3 (PO 4) 2 ‧8H 2 O was formed and resulted in the dissolution of FeS, which was favorable for the formation of Sb 2 S 3 and consequently the uptake of Sb(III). In the experiments at pH 9.0, the addition of phosphate only resulted in minor desorption of Sb(III) because FeS was very stable and consequently both Fe 3 (PO 4) 2 ‧8H 2 O and Sb 2 S 3 were unlikely to be formed. The results of this work may help to better understand the effect of phosphate on the behavior of Sb in some anoxic environments where FeS is present. [Display omitted] • The interaction of Sb(III) with FeS was significantly affected by PO 4 3-. • The effect of PO 4 3− was dependent on pH and PO 4 3− concentration. • At pH 5.5 and 7.0, high PO 4 3− loadings resulted in the formation of Fe 3 (PO 4) 2 ‧8H 2 O. • Fe 3 (PO 4) 2 ‧8H 2 O formation enhanced the formation of Sb 2 S 3 and the uptake of Sb(III). [ABSTRACT FROM AUTHOR]

Osteonecrosis of the femoral head (ONFH) is one of the most common diseases in orthopedics. In this study, we investigated the clinical effects of novel nanoscaled core decompression rods combined with mesenchymal stem cells on the treatment of the ONFH. 12 adult patients with early ONFH (at the stage of Ficat II) received the treatment using the implantation of novel nanoscaled core decompression rods combined with umbilical cord mesenchymal stem cells. The grade of the patients’ hip was scored by Harris marking system before and after the surgery, and then paired t-test was done. We assessed the curative efficiency based on the change of the patients before and after the surgery. In particular, the survival rate of femoral head was assessed at 12 months after the surgery. The results demonstrated that according to the standard of Harris Scoring, the average grade of hip joint before the surgery was 54.16 ± 4.23 points while average grade of hip joint at 12 months after the surgery was 85.28 ± 3.65 points. So, the implantation of the novel nanoscaled core decompression rods combined with mesenchymal stem cells had satisfactory clinical effects, suggesting that this implantation should be effective to treat early ONFH. [ABSTRACT FROM AUTHOR]

For deaf individuals with residual low-frequency acoustic hearing, combined use of a cochlear implant (CI) and hearing aid (HA) typically provides better speech understanding than with either device alone. Because of coarse spectral resolution, CIs do not provide fundamental frequency (F0) information that contributes to understanding of tonal languages such as Mandarin Chinese. The HA can provide good representation of F0 and, depending on the range of aided acoustic hearing, first and second formant (F1 and F2) information. In this study, Mandarin tone, vowel, and consonant recognition in quiet and noise was measured in 12 adult Mandarin-speaking bimodal listeners with the CI-only and with the CI+HA. Tone recognition was significantly better with the CI+HA in noise, but not in quiet. Vowel recognition was significantly better with the CI+HA in quiet, but not in noise. There was no significant difference in consonant recognition between the CI-only and the CI+HA in quiet or in noise. There was a wide range in bimodal benefit, with improvements often greater than 20 percentage points in some tests and conditions. The bimodal benefit was compared to CI subjects’ HA-aided pure-tone average (PTA) thresholds between 250 and 2000 Hz; subjects were divided into two groups: “better” PTA (<50 dB HL) or “poorer” PTA (>50 dB HL). The bimodal benefit differed significantly between groups only for consonant recognition. The bimodal benefit for tone recognition in quiet was significantly correlated with CI experience, suggesting that bimodal CI users learn to better combine low-frequency spectro-temporal information from acoustic hearing with temporal envelope information from electric hearing. Given the small number of subjects in this study (n = 12), further research with Chinese bimodal listeners may provide more information regarding the contribution of acoustic and electric hearing to tonal language perception. [ABSTRACT FROM AUTHOR]

Pd/graphene composites were successfully prepared in H2O/TX-100/[BMIM]PF6microemulsion in whichions were reduced in situ by TX-100 and graphene oxide was reduced by hydrazine hydrate. In the confinement region of the microemulsion, ultrafine Pd nanoparticles (NPs) supported on graphene composites were successfully prepared. The as-prepared composite materials of Pd NPs and graphene were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction. It is demonstrated that the size distribution of Pd NPs is narrow, with an average size of 4 nm. The Pd/graphene composites were tested as electrocatalysts for application in fuel cells. Cyclic voltammetry and chronoamperometry measurements show good electrocatalytic performance of the composite materials for oxidation of ethanol in alkaline medium. [ABSTRACT FROM AUTHOR]

A kind of aromatic diamine, 4′, 4″-(2, 2-diphenylethene-1, 1-diyl)dibiphenyl-4-amine (TPEDA), was successfully synthesized via Suzuki coupling reaction. The TPEDA containing nonplanar rigid moieties can be used as epoxy resins curing agent to improve the complex properties of cured composites. The curing kinetics during thermal processing of E51/TPEDA system was investigated by nonisothermal differential scanning calorimeter. The average activation energy ( E), pre-exponential factor (ln A), and reaction order ( n) calculated from the Kissinger, the Ozawa, the Friedman and the Flynn-Wall-Ozawa methods were 55.8 kJ mol, 9.4 s and 1.1, respectively. By the aid of estimated kinetic parameters, the predicted heat generation vs temperature curves fit well with the experimental data, which supported the validity of the estimated parameters and the applicability of the analysis method used in this work. By the introduction of nonplanar rigid moieties, the cured epoxy resins with TPEDA exhibited a higher glass transition temperature ( T = 258 °C), good thermal stability (≈395 °C at 10 % mass-loss), and high char yield (36.6 % at 700 °C under nitrogen) compared with conventional curing agents. [ABSTRACT FROM AUTHOR]

Based on the hourly visibility data, visibility and its changes during 2010–2020 at monthly and annual time scales over 47 international airports in China are investigated, and nine artificial-intelligence-based hourly visibility prediction models are trained (hourly data in 2018–2019) and tested (hourly data in 2020) at these airports. The analyses show that the visibility of airports in eastern and central China is at a poor level all year round, and LXA (in Lhasa) has good visibility all year round. Airports in south and the northwest China have better visibility from May to October and poorer visibility from November to April. In all months, the increasing visibility mainly occurs in the central, northeast and coastal areas of China, while decreasing visibility mainly appears in the western and northern parts of China. In spring, summer and autumn, the changes difference between east and west is particularly obvious. This East–West distribution of trends is obviously different from the North–South distribution shown by the mean. For all airports, good visibility mainly occurs from 14:00–18:00 p.m. Beijing Time, while poor visibility mainly concentrates from 22:00 p.m. to 12:00 p.m. the next day, especially between 3:00–9:00 a.m. Our proposed artificial intelligence algorithm models can be reasonably used in airport visibility prediction. In particular, most algorithm models have the best results in the visibility prediction over HFE (in Hefei) and SJW (in Shijiazhuang). On the contrary, the worst forecast results appear at LXA and LHW (in Lanzhou) airports. The prediction results of airport visibility in the cold season (October–December) are better than those in the warm season (May–September). Among the algorithm models, the prediction performance of the RF-based model is the best. [ABSTRACT FROM AUTHOR]